Эмбрионально-личиночное развитие полярной камбалы Liopsetta glacialis (Pleuronectidae) Тауйской губы (северная часть Охотского моря)

• Main Author: Юсупов, Равиль
• Format: Text
• Language: unknown
• Published: Федеральное государственное унитарное предприятие «Тихоокеанский научно-исследовательский рыбохозяйственный центр» 2010
• Subjects: ПОЛЯРНАЯ КАМБАЛА; РАЗВИТИЕ; ЭМБРИОН; ПРЕДЛИЧИНКА; Arctic; Sea ice
• Online Access: http://cyberleninka.ru/article/n/embrionalno-lichinochnoe-razvitie-polyarnoy-kambaly-liopsetta-glacialis-pleuronectidae-tauyskoy-guby-severnaya-chast-ohotskogo-morya; http://cyberleninka.ru/article_covers/12304228.png

Приводятся сведения по эмбриональному и раннему постэмбриональному развитию полярной камбалы Liopsetta glacialis. Дано морфологическое описание и установлены сроки прохождения этапов и основных стадий развития вида в условиях эксперимента. Mature impregnated eggs of arctic flounder in the Taujskaya Guba Bay belong to olygoplazmatic type and have diameter 1.620 ± 0.005 mm. The animal pole of the eggs occupies the bottom position, and the cells of periblast and blastoderm cover the yolk in bottom-up direction. The first division of zygote occurs at the age 11 hours under the temperature 2.97 ± 0.03 °C. The germ reaches the stages of early and late blastula at the age 42 and 66 hours, accordingly. In 114 hours of incubation, centrifugal redistribution of the blastoderm cells leads to formation of a distinct germinal ring on the periphery of germinal disk. Germinal strip of eggs is formed by the blastoderm cells axis-ward convergence, their migration and concentration in dorsal part of germinal ring. The vegetative pole shifts simultaneously on 130-140° from the top of egg to the bottom position because of the shift of the egg centre of gravity from its vertical axis to the area of cellular mass concentration and the embryo formation. The presence of air bubbles on external cover of the eggs is interesting. Their occurrence at the stage of late blastula and their preservation up to the beginning of organogenesis could be considered as a display of the species embrionic adaptation to specific conditions of its development in winter. These formations provide additional buoyancy for the eggs and isolate them from direct contact with rigid and overcooled surface of the sea ice during this critical period of the germ development, so they act as a provisional organ. In experimental conditions, the incubatory period of arctic flounder lasted 800 hours (2385 degree-hours). The hatched prelarvae have length from 5.7 to 6.1 mm (5.900 ± 0.007 mm) and are characterized by well-developed and mobile branchiate-maxillary system. They turn to mixed and fully external feeding in 3 and 7 days, accordingly, when their body length is 6.20 ± 0.12 and 6.48 ± 0.18 mm.